So-called "snapshot packages" at <mirror>/pub/OpenBSD/snapshots/packages/<arch> are made available on major architectures, on occasion, as a courtesy. They will never be entirely in-sync with snapshots; snapshots can be made in just a few hours, package building takes days. Many days on the slower architectures. Major architectures may have several snapshots per day, with package refreshes only once or twice per month.

Choices for -current users who upgrade from snapshot to snapshot:

Monitor snapshot package refreshes, and obtain snapshots the moment a you note a change to the snapshot packages has occured. This may not be in sync, but may be close.

Build your own packages from a synced ports tree whenever a library bump or other out-of-sync state prevents pkg_add from working.